METHODS AND RESULTS: VERBAL TOM

1. ? Woman places letter in middle basket Woman leaves room Man removes letter Man places letter in right hand basket Woman re-enters room. The Leverhulme Trust Adult aging effects on theory of mind and social cue detection.Louise H. Phillips, Roy Allen & Rebecca Bull University of Aberdeen, Scotland, UK. ADULT AGING AND THEORY OF MIND Theory of mind (ToM) is the ability to decode the mental states of others. Recent research indicates that this ability may decline as adults age, with possible differences in effects on verbal and visual ToM tasks (e.g. Slessor, Phillips & Bull, 2007). Previous studies have compared young and old adult age groups, without looking at changes across the lifespan. Also, relatively little is known of possible mechanisms that might underlie any age differences in ToM. In the current study we investigated the effects of lifespan aging on novel story and video tasks of ToM. Two research hypotheses were addressed: the first was that aging will have more effect on false belief reasoning than true belief reasoning; the second was that age differences in ToM would relate to the ability to perceive and detect emotional cues from biological (point light) motion (Heberlein, Adolphs, Tranel, & Damasio, 2004). METHODS AND RESULTS: VERBAL TOM Participants: 72 young (18-39), 46 middle-aged (40-64) and 48 older (65-88) adults. Tasks: Participants completed 16 theory of mind stories, 8 true belief (TB) and 8 false belief (FB), based on the minimal pair design (German & Hehman, 2005). Emotional biological motion perception was also assessed. METHODS AND RESULTS: VISUAL TOM Participants: 52 young (18-39), 41 middle-aged (40-64), 36 older (65-88) adults. Tasks: In total, participants completed 32 true belief (TB) and 16 false belief (FB) judgments from 24 theory of mind videos (based on ToM tasks described in Samson et al. (2005). Emotional biological motion perception was also assessed. Mary and Sandra are sitting chatting in the dining room. From there, they can just see the top of Jim’s head over the back of the sofa in the sitting room. The television is on in the sitting room but Jim is listening to his rock music through earphones. Sandra calls out to ask whether Jim will be able to pick them up from the High Street the following day. Jim nods vigorously. How likely is it that Jim will pick them up? Question: “Where will the woman look for the letter?” Fig. 4: Age differences in ToM Fig. 1: Example of a false belief story task Fig. 2: Age differences in ToM Fig. 3: Diagram of the video false belief task Results: Age influenced ToM performance, but there was no interaction between age and belief type (TB v FB). Post-hoc tests revealed that the old performed more poorly than both middle-aged and young on ToM. These age differences in performance, F(2,163) = 5.68, p < .01 became non-significant when biological motion performance was covaried, F(2,125) = 2.71, p = .07. Results: Age influenced ToM performance, but there was no interaction between age and belief type (TB v FB). Post-hoc tests revealed that the old performed more poorly than young on ToM. These age differences in performance, F(2,126) = 3.93, p < .05 disappeared when biological motion performance was covaried, F(2,124) = 1.21, NS. DISCUSSION AND CONCLUSIONS Age differences in false belief reasoning also extended to true belief tasks. This indicates that older adults are impaired in all aspects of belief reasoning, on both verbal and video tasks. For verbal tasks, middle-aged adults performed best, and older adults performed more poorly than young on both verbal and visual ToM tasks. Analyses indicated that one factor which might be important in determining older adults’ difficulties with theory of mind may be problems in decoding cues to others’ social and emotional states, as indexed by a measure of biological motion. Acknowledgements: This research was funded by the Leverhulme Trust, UK. Thanks to Pauline Insch, Kirsty Burr & Will Ogg who assisted with data collection.